This F31 study will examine a path model for the relationship of the congruence between people and their environment (P-E fit) to helping behaviors. This proposed model is derived from industrial/organizational (I/O) psychology literature. Substance abuse and dependence are common social health problems in the United States that are costly to both individuals and society. Although a variety of services have been developed to address these problems, high rates of substance use recidivism among service users are common. There is evidence that community-based addiction recovery support organizations such as sober-living houses contribute to positive abstinence outcomes. However, there is a need for research on the mechanisms related to these positive substance use outcomes, as well as ways to sustain and improve mutual-help recovery support organizations. Research has shown that individuals in recovery who engage in helping others have more positive substance use outcomes themselves. Research also suggests that helping behaviors in mutual- help groups may be important to maintaining both the therapeutic effect of groups on patient recovery and the vitality and survival of the group or organization itself. However, little research has examined factors that influence helping behaviors of mutual-help members. I/O research has found that satisfaction with and commitment to an organization are related to helping behaviors that occur within them. I/O research has also found that satisfaction and commitment are related to P-E fit - the greater the fit, the greater the satisfaction and commitment to the group/organization. One component of P-E fit that has been shown to be related to satisfaction is an organization's sufficiency in meeting member needs. I/O research has further found three components of fit to be related to commitment to organizations-incumbents' ability to meet the demands of the organization, congruence between personal and organization values, and the organization's sufficiency in meeting individual needs are all related to commitment to the organization. The proposed study will examine a path model for the relationship of these components of P-E fit to helping behaviors in a recovery home setting, with commitment to and satisfaction with the setting as mediators of that relationship. This study hypothesizes that the model will be a good fit for cross-sectional data collected from a nationwide sample (n=150) of mutual- help recovery home residents. The overall aim of this study is to explore the application of I/O theories of P-E fit to recovery home settings to better understand the factors that contribute to helping behaviors of residents.